Dental restoration procedures often require various composites to be filled into a tooth cavity or area being repaired, and subsequently cured. With certain restoration procedures, the filling and curing cycle may be repeated multiple times. The curing process is often performed using a curing tool, which emits light from a source, such as a bulb, and through a bundle of optic fibers, to thus result in a focused light output. The light output is directed at the composite and the composite is quickly cured, a process also referred to as polymerization.
To facilitate the curing process, the fiber optic bundle is often provided within a probe or light guide extending from the curing tool or gun. The probe often extends linearly from the gun with an angular can't toward a distal end to enable the dentist or dental assistant to more easily access the particular tooth being repaired.
When the light is imparted against the dental composite and tooth surface, a certain component of the light is reflected back toward the dental tool, and thus the operator. Such light can be annoying or create a distracting glare for the operator, and more problematically can be a health hazard to the operator. Many light curing guns therefore include a shield positioned to block all or some of the reflective light. Since the field of vision of the operator cannot be impaired, such shields are often transparent, but tinted to absorb certain wavelengths of light. Typically, the shield is amber or orange tinted to absorb blue light reflected from the tooth surface, while allowing other wavelengths of the reflected light to pass through the shield.
Prior art protective shields are often secured with an elastomeric grommet disposable about the probe of the curing gun. The grommet typically has a central aperture with an inner diameter slightly smaller than the outer diameter of the probe. When the grommet and shield are attached to the probe, frictional interference between the grommet and probe secures the shield in place.
However, such prior art shields have proven to be difficult to remove, difficult to sterilize, and somewhat prone to premature attachment failure. More specifically, since the grommet includes an aperture, it must be attached and removed by sliding the grommet over the tip of the probe and linearly along the length of the probe. Not only is the frictional interference significant, but the tip of the probe is often provided with a protective rim of increased diameter which the grommet must overcome during attachment and detachment. Once removed, the plastic shield can be cold-sterilized with a suitable chemical, but the elastomeric grommet, typically made of rubber, cannot be sterilized. Moreover, the elastic properties of the rubber are temporary and can result in brittleness or breakage in the grommet, or in sufficient loss in elasticity to prevent adherence between the grommet and probe, thus resulting in an ineffective shield.